1. Hulk was originally grey when he was introduced, but became green to compensate for poor color separations used to print comics in the '60s.

2. Stan Lee put a hyphen in Spider-Man's name so it would look different from Superman in print.

3. Marvel Comics and DC Comics have co-owned the trademark for the phrase "super hero" since 1981. They pursued this action because the toy company Mego, which made licensed toys of DC characters, had beat them to it. Mego gave up the trademark when the two companies threatened legal action.

5. Marvel had a rule in the mid-'70s that Wolverine did not have arm hair while in costume, but could have arm hair when he was in regular clothing.

6. Marvel published the first issue of their adaptation of Star Wars in March 1977 with a July cover date, about two months before the movie was released in theaters.

Marvel/Lucasfilm

7. Bill Sarnoff, the head of DC Comics' parent company Warner Communications, approached Marvel Comics editor-in-chief Jim Shooter in 1984 about licensing the publishing rights to the entire DC Universe. Sarnoff figured that Marvel, who dominated the market at the time, were better suited to making successful comics featuring Batman, Superman, and the Justice League. Marvel's publisher at the time, Jim Galton, declined Sarnoff's offer, thinking that those comics weren't selling well because the characters weren't very good.

8. Marvel Comics founder Martin Goodman was meant to be aboard the Hindenberg on the day the ship famously crashed, but changed his travel plans at the last minute.

9. Martin Goodman tried to talk Stan Lee and Steve Ditko out of introducing Spider-Man because he insisted that kids hate spiders.

11. Jim Shooter, Marvel's editor-in-chief in the '80s, bought the idea for Spider-Man's black costume from a fan for $220, and gave the fan a shot at writing the comic, though that didn't work out. The black costume was introduced as an alien "symbiote" and eventually became one of Spider-Man's most famous villains, Venom.

Marvel

12. Though G.I. Joe is owned by Hasbro, the majority of the characters and mythology for the toys and animated series were created mainly by Larry Hama, the writer of the licensed comics published by Marvel Comics. Editor-in-chief Jim Shooter was the one to suggest that G.I. Joe was a team rather than the name of a particular person.

14. Similarly, the backstory for Transformers and most of the original characters including Optimus Prime and Megatron, were created by Marvel editors Jim Shooter and Denny O'Neil along with writer Bob Budiansky.

15. George Romero, the director of Night of the Living Dead, worked with Marvel for two years on a project that would've debuted as a comic and movie simultaneously, but plans were dropped after Romero's sequel, Day of the Dead, flopped in 1985.

16. Marvel Comics owned the rights to the word "zombie" from 1975 through 1996, when they realized it was impossible to enforce the trademark.

18. Hulk was given the name Robert Bruce Banner because Stan Lee accidentally wrote some comics with his name as Bob Banner rather than Bruce Banner, as he was originally introduced. Lee retroactively gave him the new name so both were correct.

19. Kitty Pryde was named after one of John Byrne's classmates at the Alberta College of Art, but the real Kitty Pryde changed her name in the early '90s to avoid unwanted attention from comics fans.

20. Dave Cockrum designed early versions of key X-Men characters Nightcrawler and Storm for use in The Outsiders, a spinoff of DC's Legion of Super-Heroes.

21. When Nick Fury was recreated for Marvel's "Ultimate universe" in 2000, creators Mark Millar and Bryan Hitch deliberately modeled the traditionally white character on Samuel L. Jackson. This led to Jackson eventually getting cast as Fury in the Marvel cinematic universe.

22. The Human Torch was not used in the '70s Fantastic Four cartoon because Universal Studios had licensed the character and blocked the use of him in the show, and not because the network was afraid children would light themselves on fire emulating the hero.

23. Marvel Comics was prohibited from featuring werewolves in comics by the Comics Code Authority from 1954 through 1971. This pushed Marvel creators to be more imaginative, and resulted in the creation of Sauron, a character that's basically a were-pterodactyl with vampiric powers, in the pages of X-Men in 1969.

24. She-Hulk was created after Marvel learned of a plan to introduce a female Hulk in the popular Incredible Hulk tv series. They rushed the first issue of The Savage She-Hulk into production so they could hold the copyright and trademark.

25. Loki's first appearance in the Marvel Universe predates that of his brother Thor's first appearance by 13 years.

26. Rob Liefeld placed an ad for a comic called Executioners in the Comic Buyers Guide. It was a blatant rip-off of his own work on X-Force, which prompted Marvel to threaten legal action. Liefeld dropped the project entirely and ended up doing Youngblood instead.

27. Avengers writer Steve Englehart made a point of portraying Beast as a stoner in the '70s, though he was not allowed to make direct references to drugs. Englehart had the character portrayed reading Carlos Castaneda books and listening to Stevie Wonder, which was meant to convey that he was a "young, intellectual guy who'd gotten hip."

28. The X-Men character Dazzler was actually created to serve as a multi-media cross-promotion between Casablanca Records and Marvel Comics. She was originally planned to have a real life equivalent with a record and a movie, but both ideas were dropped when disco started falling out of fashion.

29. Scott Lobdell became the main writer of the X-Men franchise because he happened to be in the right place at the right time when Chris Claremont's intended successor, John Byrne, quit after being asked to script an entire issue overnight. Lobdell, who was inexperienced and hungry for work, jumped at the opportunity.

30. Marvel got around a law that increases taxes on toys that resemble humans by claiming that X-Men figures were mutants, not humans.

31. Marvel are basically required to publish comics featuring someone, anyone, called Captain Marvel in order to hold on to the trademark. The first Captain Marvel was introduced in the late '60s when Marvel learned that DC was planning to revive Fawcett's Captain Marvel from the '40s, and could only hold on to the copyright if they were publishing a character with the name. When DC brought the character back, they ended up calling comics featuring him Shazam, since they couldn't use Captain Marvel as a title. (When DC rebooted its line of comics in 2011, they decided to just change the character's name to Shazam.)

32. When Todd McFarlane, Jim Lee, Rob Liefeld, and four other major Marvel artists left the company to form Image Comics in 1992, Marvel's stock price immediately dropped more than $11 per share.

33. Game of Thrones author George R.R. Martin regularly wrote in to Marvel's letter columns in the '60s.

Marvel

34. Marvel had Cyclops and Jean Grey get married in the comics because they found out that the producers of X-Men: The Animated Series intended to have them wed in the show's second season.

35. Marvel continued to use Godzilla in the mid-'80s even though their license to publish comics featuing the character had expired.

36. And, of course, Captain America and Dr. Strange were once in a band with Linda Rondstadt and C-3PO from Star Wars.